DIVERSE WATER QUALITY AND NUTRIENT PROFILE IN GEOLOGICALLY
VARIANT SURFACE WATER AND WETLANDS AT MENDON PONDS PARK
Padmini Das1, PhD., Thomas K. Caraher1, Faith E. Downes1 , MaryLynn Eddington1, Daryn M. Loy1, Daniel J. Tofil1
Antoine Audet1, , Meghan E. Denny1, Chelsea L. Diekvoss1, , , Martin M. Glazer1, , Annalissa M. MacPherson1, Eileen E. Pelkey1, and Max W. Randolph1
Abstract
of Biology, Nazareth College, Rochester, NY 14618, United States
Objectives
This study investigates various water quality parameters in surface water and wetlands in a geologically diverse area
in Mendon Ponds Park, Rochester, NY. It also determines the trophic profile of these water bodies in terms of nitrate
and phosphate to understand their eutrophication potential. The unique water signatures of these water bodies lie in
their geological origin through glacial melting since last ice age. Different pattern of aquatic and wetland flora and
fauna indicates variance in their water quality and nutrient profiles. To validate this hypothesis, two water bodies, a
pond (Deep Pond) and a kettle pond (Devil’s Bathtub) that are separated by an esker; and two wetlands, a vernal pool
and a bog (Kennedy’s Bog) were selected. Triplicate samples were collected from each of the sample locations, which
were carefully selected, based on their accessibility, to attain adequate representation. All samples were analyzed for
pH, electrical conductivity (EC), dissolved oxygen (DO), nitrate, and total phosphorus (TP) as a measure of
phosphate. The GPS coordinate of each sample location is recorded to maintain the uniformity of repeated sampling
at different seasons in future. Results showed unique and diverse characteristics of water at each sampling location.
For instance, the pH of the kettle pond is lower but did not vary significantly (p>0.05) as compared to the Deep Pond
and the vernal pool. However, as expected, the pH of the bog is significantly lower (p<0.0001) than the rest. DO is
significantly lower (p<0.0001) in the vernal pool as compared to others; this can be explained by the dead leaves
covering most of the air-water interface at the surface of the pool. The EC, nitrate, and the TP of Deep Pond is
significantly higher (p<0.0001) than the kettle pond and the vernal pool, which are segregated by an esker that
restricts the input flow from the surrounding land. The bog water also showed its characteristic low nutrient profile.
Statistical correlation between these water quality parameters also suggests information about the potential sources of
nutrients from the surrounding area. The data generated in this preliminary study are highly encouraging and set
base to achieve our long-term goal of studying water quality and trophic profile of these geologically diverse surface
water and wetlands in Mendon Ponds Park, as functions of seasonality and occurrence of big storm events.
Experimental Design & Analysis
The specific objectives for this study are to :
1.
Investigate the various water quality parameters in surface water and
wetlands.
2.
Create a trophic profile through measuring the nutrients like nitrate and total
phosphorus.
3.
Determine the statistical correlation of these measured water qualities to
understand the potential sources of the nutrients.
2.5
pH
Measured using a VWR Scientific pH probe. Three point calibration was performed and quality control (QC )
samples were checked ((100 + 1)%) before, after, and in between 10 samples.
Electrical
Conductivity (EC)
Measured using a Vernier conductivity probe. Two point calibration was performed and quality control (QC )
samples were checked ((100 + 1)%) before, after, and in between 10 samples.
Dissolved Oxygen
(DO)
Measured using a Vernier DO probe. Two point calibration was performed and quality control (QC ) samples
were checked ((100 + 5)%) before, after, and in between 10 samples.
Nitrate
Measured using a Vernier nitrate probe. Three point calibration was performed and quality control (QC )
samples were checked ((100 + 5)%) before, after, and in between 10 samples.
Total Phosphorus
Measured using a microplate method (D’Angelo et al., 2001). Five point calibration was performed and
several quality control (QC ) samples were checked ((100 + 5)%).
Statistical
Analysis
Statistical Analyses were performed using the JMP.In version 11. Q tests were performed on all data to
eliminate possible outliers at the 95% confidence intervals. Mean values were developed along with their
standard deviations. Tukey Kramer honest significant difference test was conducted to evaluate the
significant differences along treatment means. Pairwise multivariate correlation was performed using all the
water quality and nutrient data.
Absorbance (nm)
1Department
y = 0.001x + 0.1311
R² = 0.9971
2
1.5
1
0.5
0
0
Results & Discussion
Figure 2. Topographic map of
the study area at Mendon
Ponds Park showing the
unique geography of the
sampling locations.
Devil’s Bathtub
A Kettle Pond
Figure 6. Dissolved Oxygen (mg/L) of water at various sampling
locations. Data are expressed as mean (n=5) + one standard
deviation. Mean comparison was conducted using Tukey Kramer
honest significant difference (HSD) test. Different letters express
significant difference among the sample means.
Figure 7. Electrical Conductivity (μS/cm) of water at various
sampling locations. Data are expressed as mean (n=5) + one
standard deviation. Mean comparison was conducted using
Tukey Kramer honest significant difference (HSD) test. Different
letters express significant difference among the sample means.
The pH varies significantly (p<0.0001) among different sampling
sites.
The DO varies significantly (p<0.0001) among different sampling
sites.
The EC varies significantly (p<0.0001) among different sampling
sites.
The pH of these water bodies provides evidence as to why certain
species exist or don’t exist at respective locations.
The highest DO of Deep Pond exhibits characteristics of a healthy
aquatic system that sustains a diverse flora and fauna, which was
observed during the study period.
The Deep Pond shows the highest electrical conductivity which
suggests presence of most ions in it as compared to the other
locations.
The vernal pool had the lowest dissolved oxygen, significantly
lower as compared to any other sampling locations. This can be
attributed to the presence of decomposing leaves covering a majority
of the water surface. As evident in figure 3, the dark color of water,
which accounts for the decomposed organic debris, also explains the
least DO measured in the vernal pool.
EC showed significantly (p<0.05) strong correlation with nitrate
and phosphate (table 2), which explains the higher EC in Deep pond
and least in Devil’s bathtub and the bog.
The bog was by far the most acidic; consequently, it contains
organisms that could survive under this acidic condition.
Dwarf larch pine, cotton grass, and carnivorous plants like pitcher
plant, sundew were the most observed plant species in the bog.
The pH of Deep Pond is slightly alkaline, which expresses the
characteristic water signature of the area as it contains limestone.
In comparison, Devil’s Bathtub and the vernal pool exhibited lesser
pH, which probably accounts for their stagnant nature and higher
decomposition, resulting in production of more organic acids.
The DO profile of water at these sampling locations corroborates
well with the species diversity observed in these unique water
bodies/wetlands.
Variable
by Variable
Correlation Coefficient (r)
pH
EC
EC
Nitrate
Nitrate
Nitrate
Phosphate
Phosphate
Phosphate
Phosphate
DO
DO
pH
DO
pH
EC
DO
pH
EC
Nitrate
0.44
0.93
0.63
0.95*
0.55
0.99**
0.91
0.76
0.97*
0.95*
Deep Pond
Kennedy’s Bog
Vernal Pool
Mayer TD. 2005. Water-Quality Impacts of Wetland Management in The Lower Klamath National
Wildlife Refuge, Oregon and California, USA. Wetlands, 25(3): 97-712
Whigham DW, Jordan TE. 2003. Isolate Wetlands and Water Quality. Wetlands, 23(3):541-549.
D'Angelo, E, Crutchfield, J, & Vandiviere, M. 2001. Rapid, Sensitive, Microscale Determination of
Phosphate in Water and Soil. Journal of Environmental Quality, 30(6): 2206-2209.
http://cfpub.epa.gov/wqsits/nnc-development/
http://www.gpsrunner.net/tom_perry/garmin-news.htm
http://www2.monroecounty.gov/parks-mendonponds.php
Figure 5. pH of water at various sampling locations. Data are
expressed as mean (n=5) + one standard deviation. Mean
comparison was conducted using Tukey Kramer honest
significant difference (HSD) test. Different letters express
significant differences among the sample means.
Table 2.
Pairwise
Correlation.
* shows the
level of
significance .
* (95%); **
(99%)
2000
2500
Conclusion
References
(Source - http://www.gpsrunner.net/tom_perry/garminnews.htm)
1500
Figure 4. Standard curve for total phosphorus (at 595
nm)
Figure 3. Different sampling locations
Figure 1. Sample collection map
of different locations at Mendon
Ponds Park. Latitudes and
longitudes of each sampling site
was recorded using a field GPS
meter and the map was created
marking the locations at Google
Earth.
1000
Concentration of Phosphates (µg/L)
Introduction
• Mendon Ponds Park is a National Natural Historic Landmark due to its 2500 acres of woodlands, ponds, wetlands,
and glacially created landforms.
• Samples were collected from two different water bodies, a pond (Deep Pond) and a kettle pond (Devil’s Bathtub) that
are separated by an esker; and two wetlands, a vernal pool, and a bog (Kennedy’s Bog).
• Each water body and their immediate surroundings displayed significant variation in flora and fauna, indicating a
variance in water quality and nutrient profiles as well.
• The water quality of the samples collected was analyzed based on five different criteria: pH, electrical conductivity
(EC), nitrate content, total phosphorus content (TP), and dissolved oxygen content (DO).
500
Figure 8. Nitrate (mg/L) of water at various sampling locations.
Data are expressed as mean (n=5) + one standard deviation.
Mean comparison was conducted using Tukey Kramer honest
significant difference (HSD) test. Different letters express
significant difference among the sample means.
Overall, the results from this
experiment show that the water quality
varies significantly among the tested
surface water/wetlands at Mendon
Ponds Park attributing to its unique
geographic characteristics.
The trophic profile of the Deep Pond
shows that it is at the greatest risk of
eutrophication as compared to the
other water bodies observed.
The future directions that can be taken
with this project would be to sample
the same locations at different times
throughout the year, to monitor
seasonal change. Another experiment
aims to measure the trophic profiles
after major storm events.
Figure 9. Total Phosphorous Concentration (µg/L) of water at
various sampling locations. Data are expressed as mean (n=5) +
one standard deviation. Mean comparison was conducted using
Tukey Kramer honest significant difference (HSD) test. Different
letters express significant difference among the sample means.
Trophic Profiles
The trophic profile of the tested surface water/wetlands are expressed as nitrates (Figure 8) and total phosphorus (as an account for phosphate;
Figure 9). Like the other water quality parameters, trophic profiles also vary significantly (p<0.0001) among different sampling sites.
The high trophic profile for Deep Pond exhibits evidences of fertilizer run-offs from the surrounding area, which is largely covered by
farmlands. Concentrations of both nitrate and total P are much higher than the advisory level (20 µg/L), establishing the need for precautionary
measures and planning to prevent subsequent eutrophication of the pond over time.
The striking difference between Devil’s Bathtub and the Deep Pond in their trophic profile is attributed to their physical separation by the
esker, which restricts the south-westward flow of water and runoffs.
The bog exhibits its characteristic low nutrient profile. The very high level of TP is attributed to the closest contact between its water and
sediments (as a result of minimal depth), which serves as a great sink of phosphate in lentic systems.
Significant nitrate-phosphate correlation (Table 2) indicates a similar source, potentially fertilizer runoffs from the surrounding large
farmlands.